Place the cake on a clean work surface. Use the bread knife and trim the top of the cake to make level. Cut the cake in half lengthwise.

Spread some of the vanilla frosting on one cut side of cake. Place the other cake on top, cut side down and sandwich together. Cut the cake into thirds, crosswise, to make 3 squares. Trim cakes again to make them as square as possible.

Frosting the cake:

Spoon 3/4 cup of the vanilla frosting into a zip lock bag. Set aside.

Divide the remaining frosting between 3 bowls. Tint each bowl a different pastel color with the food coloring. Cover the bowls with plastic wrap to prevent drying.

Spread one cake with one of bowl of tined frosting and make smooth. Repeat with the other cakes and tinted frostings.

To complete the cake:

Unwrap the fruit chews. Microwave 4 fruit chews at a time for no more than 3 seconds to soften. Press together and roll out to a 4-inch circle. Use the cookie cutters to cut out desired shape. Transfer shape to a cookie sheet lined with parchment paper. Repeat with the remaining fruit chews and scraps to make 15 shapes.

Press the fruit chew cut outs onto the center of each side of the frosted cakes. Add some vanilla frosting to help secure if necessary.

Snip a small corner from the bag with the vanilla frosting. Pipe lines of vanilla frosting all along the edge of cakes.

Use a spatula to transfer cakes to a serving platter, stacking one of the cakes on the other 2 if desired.